US4379218A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluxless ion beam soldering process
Assignee: International Business Machines Corp
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Filing: 1981-06-30
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Granted: 1983-04-05
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Expires: 2001-06-30
Abstract
Abstract A method for fluxlessly joining members having relatively low melting materials is provided. The members to be joined are exposed to ion beam radiation of sufficient intensity and a time sufficient to cause cleaning of the low melting materials after cooling. The members are then placed into juxtaposition with each other and again exposed to ion beam radiation of an intensity and for a time sufficient to cause reflow of the low melting materials which upon cooling joins said members.
Inventors
- 👤 Kurt R. Grebe
- 👤 James M. E. Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:32
CPC Classifications
B; B23; B23K; B23K1/00; B23K1/20; B23K1/206; B23K1/005; B23K17/00; C; C23; C23G; C23G5/00; H; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/097; B23K2101/00; B23K2101/36; B23K2101/40; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/3489; H10W72/00; H10W72/01; H10W72/012; H10W72/01271; H10W72/071; H10W72/0711; H10W72/07118; H10W72/07125; H10W72/072; H10W72/07231; H10W72/07236
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
139 words
A process for fluxlessly joining members together including the steps of: (a) providing a first member having disposed a plurality of pads of a low melting material; (b) providing a second member having disposed a plurality of matching pads to which pads of said first member is to be joined; (c) simultaneously exposing said pads on said first and second members to an ion beam of sufficient energy and for a time sufficient to clean and melt said pads; (d) cooling said exposed pads to cause said pads to solidify; (e) placing the pads of said first member in juxtaposition to matching pads of said second member; and thereafter (f) exposing said pads to ion beam radiation of sufficient energy and for a time sufficient to cause said pads to reflow whereby upon cooling said matching pads are joined.
Claim 2
Dependent Claim
139 words
A process for fluxlessly joining members together including the steps of: (a) providing a first member having disposed a plurality of pads of a low melting material; (b) providing a second member having disposed a plurality of matching pads to which pads of said first member is to be joined; (c) simultaneously exposing said pads on said first and second members to an ion beam of sufficient energy and for a time sufficient to clean and melt said pads; (d) cooling said exposed pads to cause said pads to solidify; (e) placing the pads of said first member in juxtaposition to matching pads of said second member; and thereafter (f) exposing said pads to ion beam radiation of sufficient energy and for a time sufficient to cause said pads to reflow whereby upon cooling said matching pads are joined.
Claim 3
Dependent Claim
21 words
A method in accordance to claim 1 wherein said low melting material has a melting point of less than 1000° C.
Claim 4
Dependent Claim
16 words
A method in accordance to claim 1 wherein said low melting material is a solder alloy.
Claim 5
Dependent Claim
15 words
A method in accordance to claim 3 wherein said solder alloy is a PbSn alloy.
Claim 6
Dependent Claim
30 words
A method in accordance to claim 3 wherein said ion beam intensity step c is in the range of from about 1 mA/cm 2 to about 10 mA/cm 2 .
Claim 7
Dependent Claim
25 words
A method in accordance to claim 5 wherein the time to clean and melt said pads is from about 1 sec to about 20 secs.
Claim 8
Dependent Claim
25 words
A method in accordance to claim 6 wherein the ion beam intensity in step f is from about 1 to about 10 mA/cm 2 .
Claim 9
Dependent Claim
22 words
A method in accordance to claim 7 wherein the time in step f is from about 5 secs. to about 200 secs.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-04 | 1986-10-04 | 1987-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-04 | 1990-10-04 | 1991-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-04 | 1994-10-04 | 1995-04-05 | $7700.00 | Window Closed / Lapsed |